12
installation
Safety Valve Discharge:
The discharge should terminate facing downward on the
exterior of the building in a position where discharging
(possibly boiling water & steam) will not create danger or
nuisance, but in an easily visible position, and not cause
damage to electrical components and wiring.
The discharge must not be over an entrance or a window or
any other type of public access.
Air Release Points:
These must be fi tted at all high points where air naturally
collects and must be sited to facilitate complete fi lling of
the system.
The appliance has an integral sealed expansion vessel to
accommodate the increase of water volume when the
system is heated.
It can accept up to 8 litres (1.8 gal) of expansion water. If
the heating circuit has an unusually high water content,
calculate the total expansion and add an additional sealed
expansion vessel with adequate capacity. This should be
located on the return pipe work as close as possible to the
pump inlet.
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1100 1200
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mbar
l/h
Mains Water Feed - Central Heating:
A method for initially fi lling the heating
system is supplied with the connection kit.
The fi lling loop is connected between the
cold water inlet and the central heating
fl ow connections, and incorporates a non-
return valve. To operate the fi lling loop,
it is necessary to open both quarter turn
handles, once the required pressure has
been achieved, close both handles and
disconnect the hose in accordance with
water byelaws. Note: The installer should
ensure that there are no leaks as frequent
fi lling of the heating system can lead to
premature scaling of the main exchanger
and failure of hydraulic components.
Domestic Water:
The domestic water must be in accordance
with the relevant recommendation of
BS 5546:1990. Copper tubing to BS EN
1057:1996 is recommended for water
carrying pipe work and must be used for
pipe work carrying drinking water, a scale
reducer should also be used to reduce the
risk of scale forming in the domestic side
of the heat exchanger.
Residual Head of the Boiler ΔT 20°C
Fig. 9
Fig. 10
GAS
GAS
